The subject of getting Adobe’s Flash on Apple’s iPhone, just won’t go away, and now there’s new comments from Adobe (NSDQ: ADBE) Systems’ CEO Shantanu Narayen to get the rumor mill buzzing again. In a Bloomberg TV interview from the World Economic Forum in Davos, Switzerland, he said: “It’s a hard technical challenge, and that’s part of the reason Apple (NSDQ: AAPL) and Adobe are collaborating…The ball is in our court. The onus is on us to deliver.” Both Adobe’s and Apple’s comments regarding Flash technology on the iPhone have been all over the map. Adobe has said at times that it would be easy and difficult, and Apple has criticized that the full Flash version is too slow for the iPhone, while Flash Lite isn’t capable enough. Narayen’s most recent comments suggest that Adobe wasn’t able to port Flash to the iPhone just using the available developer kit, and that the two companies are having to work more closely together, and that Adobe is working hard to deliver.